Coil eos wireless apparatus



INVENTOR. flea 6? Mecc BY Y ATTORNEY-9' F. G. NIECE COIL FOR WIRELESS APPARATUS Filed Dec. 26. 1922 Patented Nov. 1, 1927.

UNITED STATES 1,647,744 PATENT OFFICE.

FRED G. NIECE, OF CLEVELAND, OHIO.

' COIL FOB-WIRELESS APPARATUS.

Application filed December 26, 1922. Serial No. 609,159.

This invention relates to an improved coil for radio apparatus and, an improved method and means for winding and mounting the same. More particularly it comprises a coil having a minimum amount of distributed capacity for the wave length for which itis designed.

' The value of air. insulation in connection with coils for radio apparatus, particularly for receiving sets, has been recognized through the development of the honey-comb type of coil. Such coils, however,'are best suited to long wave-lengths, the large air cores embodied in their design making them lesseffective-for. short .wave reception than the spider-web type of.-;coil. ,The spiderweb type of coil, as heretofore constructed, requires an internal spideror similar support which reduces the efiiciencyof the coil by addingto its distributed. capacity, although it hasa muchbroader effective field than the honey-comb type of coil. Moreover, the honey-comb type of coil,.as mounted in tapes and bands, isnot free of capacity effects which seriously impair its value within-the limit of itsdesign. I

The present invention has for its object to improve-suchcoils in general andto obviate the difficulties referred-to, and to produce a coil for radio apparatus having a minimumof distributed capacityand a maximumof self-inductance. Itisaalso an objectofthe invention to suspend the coilof the-circumferentially interwoven or intercoiled type by means of threads or similar flexible connections from a support spaced from the coil an adequate distance to provide an insulating air gap. Other objects of the invention will appear in the course of the following description. To the accomplishment of the foregoing and related ends, said inventiomthen, consists of the means and method hereinafter-fully described and particularly pointed out in the claims.

The annexed drawing and the following description set forth in detail certain structureembodying the; invention and method of making the same, such disclosed means constituting, however, but several of various structural forms and methods of making the same, in which the principle of the invention may be used.

In said annexed. drawing:

Fig. 1 is a side elevation of my preferred type of coil and mounting in the usual vertical position as mounted on the panel of a receiving set; Fig. 2 is a side elevation of means for winding a coil of the type shown in Fig. 1; Fig. 3 is a development of a section of the coil shown in Fig. 2, taken along the line 33 looking in the direction of the arrows; Fig. 4 is a side elevation of a coil of the type shown in Fig. 1 supported upon an internal mounting; Fig. 5 is a transverse longitudinal sectional view taken along the line 5-5 shown in Fig. 4; Fig. 6 is a side elevation of a modified type of coil, the windings corresponding to the Gramme ring; Fig. 7 is a transverse view of the Gramme type of coil illustrated in Fig. 6 when formed with a circular cross section; F ig.;8 is a view of said type of coil shown in Fig. 6 when formed with flattened sides so as to present an elliptical cross section; Fig. 9 is a perspective view showing a still further modified type of coil wherein the windings are of substantially figure 8 cross section, and Fig. 10 is a side elevation showing a coil supported upon an internal and external mounting.

As is clearly shown in Fig. l of the drawing, the preferred form of coil 1, and mounting made in accordance with the invention, is a coil of annular outline and narrow rectangular cross section which is suspended within an-annulus 2 preferably formed of rigid insulating material of somewhat larger diameter than the coil. Flexible means 3 comprising thread of adequate strength is interlaced, as is clearly shown in the drawing, through the series of aperturesl formed in the circumference of the supporting annulus and through the inner opening of the coil successively so as tosupport the coil concentrically with the mounting.

At one side of the annulus a supporting arm 5 is provided which may be hingedly or otherwise connected with the usual panel of a radio receiving set where said coil is to be used for such purpose. It is not intended, however, to limitthe use of the coil to the particular purpose referred to, inasmuch as the invention contemplates the use of this type of coil wherever the-reduction of distributed capacity to a minimum is indicated as proper designing. Opposite the point of connection of the supporting arm a finger pin 6 may be provided, said pin serving as one means of shifting the coil laterally where it is used in a three circuit or similar type of receiving set.

In Fig. 4 of the drawing is shown a modified form of mounting for the coil wherein the same is supported internallyfinstea'd of externally, by means of an internal dislc't',

preferably formed of insulating material spaced at every point out of contact with the coil. said coil suspended in spaced relation about said disk by means of loops encircling said coil and passing through apertures 9 formed adjacent the circumference of said disk. As shown in Figs. 4 and 5, said disk is adapted to be secured to the panel by means of a special support preferably formed of insulating material. Said support is preferably an arm 11 having an integral disk-like terminal 12, to which the supporting disk- I of the coil is attached by means of bolts'14 and spacing bushings 15. Y

In place of either of the methods of mounting the support heretofore mentioned, the coil may be supported from both internal and external supports of the character described as is shown in Fig. 10, .through the interlacing of flexible connections 3, 8, between said coil and said supports. Theform first described, however, is my preferred form, inasmuch as it secures greater rigidity for the outer edges of the coil and serves-as a guard for the coil itself, as well as removes as far from'the coil as'possible'all elements which would 'seriously afiect its dis tributed capacity. p 4

In Figs. 6, 7 and 8, there is-illustrated a coil 20 of the Gramme ring typefof-construction which may be substituted-fondle; preferred type of coil'alreadydescribedz As shown in Figs. 6 and 7, the coil preferably is formed of a single wirewound aboutaci'role of a given diameter and continued as a heh ical winding until an adequate amountgpf wire has been incorporatedin t-lie coi'lor the purpose for which it is'designed." .-'=In order to diminish the air core of the coil,-as-wellas increase its effective field vvit-h respect'to adjacent inductances, the coil just described may be formed with flattened-*sides- 21', as shown in Fig. 8 of the drawing.

The type of winding 22, shown in Fig; =9 of the drawing, has the advantage of the cir cular form of Grannne ring'coil' and'at the same time requires no flattening of the sides, inasmuch as the figure 8 outline of the windings serves to present'a coil of narrow transverse dimensions. It is obvious that the magnetic fields of the outer and inner parts of the coil are reversed with respect to each other and mutually interact to enhance the total inductance of the coil.

lVhile the invention is not restricted to'one method of winding the coil, there is included herein a method which necessarily results in the production of the preferred type of coil.

Flexible means 8 are used to hold wheel, and winding a wire 34 about two such pegs 35, 36, croming to the opposite side and winding said wire about the two adjacent pegs 37, 38, and repeating the process until the circuit is complete, ati'ords one of the simplest methods ofconstructing a coil which will have a high degree of rigidity when suitably tied with thread. An uneven number of pegsis provided so that when the circuit of the-cylinder has been completed the second layer of winding will be about a differentpair-ofpegs than the first and the winding will be shifted one peg alternately throughout the structure of the coil. When the'coilis built up to the desired size, the pegs are successively withdrawn from the apertures, the cylinder or mandrel is removedfrom the center of the coil, and thread of suitable-strength is interlaced about the windings passing downwardly through each aperture formerly occupied by a peg and upwardly through the adjacent aperture thereto =and thence: downwardly once more throughthe original aperture and in a similar manner throughout the circumference of the coil, certain of the loops ll so formed extending downwardly and the adjacent loops 42-iformed in said win thread extending upwardly. Theends of the thread aresecurelyitied and a'coil, having each of its circumi'erential-ilayers firmly held to the adjacentlayers, isprovided. The coil so formed is self-supporting and of a very high degree of rigidity. The coil is then connected in spacedrelation to its mounting, as has already-been described, for use in whatever unit-0t radiozapparatus that may be desired. "Other forms may be employed embodying the feat-uresof my invention instead of the one here-explained, change being made in the form or construction, provided the elements stated by any of'the following claims or the equi-valentof-sueh stated elements be employed, whether produced by my preferred method or by others embodying steps equivalent to those stated in the following claims.

I therefore particularly point out and dis tinctly claim as my invention p 1. In an article of the character described, the combination of an annular coil the windings of which co-operate to form loops, arigid mounting therefor spaced from said coil, andmeans for connecting said coil ata plurality of points with said mounting.

2. In an article of the character described, the combination of an annular coil the windings of which co-operate to form loops, a rigid mounting therefor uniformly spaced from said coil, and flexible means for connecting said coil at a plurality of points with said mounting.

3. In an article of the character described, the combination of a circumferentially interwoven coil, a rigid mounting therefor spaced from said coil, and means for connecting said coil at a plurality of points with said mounting.

4. In an article of the character described, the combination of a circumferentially interwoven coil, a rigid mounting therefor positioned outwardly of and spaced from said coil, and means for connecting said coil at 19 a plurality of points with said mounting.

5. In an article of the character described, the combination of a circumferentially interwoven coil, a rigid mounting therefor positioned inwardly of and spaced from said coil, and means for connecting said coil at a plurality of points with said mounting.

6. In an article of the character described, the combination of a circumferentially interwoven coil, a rigid mounting therefor p0- sitioned outwardly and inwardly thereof and spaced from said coil, and means for connecting said coil at a plurality of points with said mounting.

Signed by me, this 18th day of December, 1922.

FRED G. NIECE. 

